<!DOCTYPE html>

<head>
  <meta charset="utf-8">
  <style>
    .link {
      fill: none;
      stroke: #666;
      stroke-width: 1.5px;
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    #licensing {
      fill: green;
    }

    .link.licensing {
      stroke: green;
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    .link.resolved {
      stroke-dasharray: 0, 2 1;
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      fill: #ccc;
      stroke: #333;
      stroke-width: 1.5px;
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      font: 10px sans-serif;
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      text-shadow: 0 1px 0 #fff, 1px 0 0 #fff, 0 -1px 0 #fff, -1px 0 0 #fff;
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</head>

<body>
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  <script>

    // http://blog.thomsonreuters.com/index.php/mobile-patent-suits-graphic-of-the-day/
    var links = [
      { source: "Microsoft", target: "Amazon", type: "licensing" },
      { source: "Microsoft", target: "HTC", type: "licensing" },
      { source: "Samsung", target: "Apple", type: "suit" },
      { source: "Motorola", target: "Apple", type: "suit" },
      { source: "Nokia", target: "Apple", type: "resolved" },
      { source: "HTC", target: "Apple", type: "suit" },
      { source: "Kodak", target: "Apple", type: "suit" },
      { source: "Microsoft", target: "Barnes & Noble", type: "suit" },
      { source: "Microsoft", target: "Foxconn", type: "suit" },
      { source: "Oracle", target: "Google", type: "suit" },
      { source: "Apple", target: "HTC", type: "suit" },
      { source: "Microsoft", target: "Inventec", type: "suit" },
      { source: "Samsung", target: "Kodak", type: "resolved" },
      { source: "LG", target: "Kodak", type: "resolved" },
      { source: "RIM", target: "Kodak", type: "suit" },
      { source: "Sony", target: "LG", type: "suit" },
      { source: "Kodak", target: "LG", type: "resolved" },
      { source: "Apple", target: "Nokia", type: "resolved" },
      { source: "Qualcomm", target: "Nokia", type: "resolved" },
      { source: "Apple", target: "Motorola", type: "suit" },
      { source: "Microsoft", target: "Motorola", type: "suit" },
      { source: "Motorola", target: "Microsoft", type: "suit" },
      { source: "Huawei", target: "ZTE", type: "suit" },
      { source: "Ericsson", target: "ZTE", type: "suit" },
      { source: "Kodak", target: "Samsung", type: "resolved" },
      { source: "Apple", target: "Samsung", type: "suit" },
      { source: "Kodak", target: "RIM", type: "suit" },
      { source: "Nokia", target: "Qualcomm", type: "suit" }
    ];

    var nodes = {};

    // Compute the distinct nodes from the links.
    links.forEach(function (link) {
      link.source = nodes[link.source] || (nodes[link.source] = { name: link.source });
      link.target = nodes[link.target] || (nodes[link.target] = { name: link.target });
    });

    var width = 960,
      height = 500;

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      .nodes(d3.values(nodes))
      .links(links)
      .size([width, height])
      .linkDistance(60)
      .charge(-300)
      .on("tick", tick)
      .start();

    var svg = d3.select("body")
      .append("svg")
      .attr("width", width)
      .attr("height", height);

    // Per-type markers, as they don't inherit styles.
    svg.append("defs")
      .selectAll("marker")
      .data(["suit", "licensing", "resolved"])
      .enter().append("marker")
      .attr("id", function (d) { return d; })
      .attr("viewBox", "0 -5 10 10")
      .attr("refX", 15)
      .attr("refY", -1.5)
      .attr("markerWidth", 6)
      .attr("markerHeight", 6)
      .attr("orient", "auto")
      .append("path")
      .attr("d", "M0,-5L10,0L0,5");

    var path = svg.append("g")
      .selectAll("path")
      .data(force.links())
      .enter().append("path")
      .attr("class", function (d) { return "link " + d.type; })
      .attr("marker-end", function (d) { return "url(#" + d.type + ")"; });

    var circle = svg.append("g")
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      .attr("r", 6)
      .call(force.drag);

    var text = svg.append("g")
      .selectAll("text")
      .data(force.nodes())
      .enter().append("text")
      .attr("x", 8)
      .attr("y", ".31em")
      .text(function (d) { return d.name; });

    // Use elliptical arc path segments to doubly-encode directionality.
    function tick() {
      path.attr("d", linkArc);
      circle.attr("transform", transform);
      text.attr("transform", transform);
    }

    function linkArc(d) {
      var dx = d.target.x - d.source.x,
        dy = d.target.y - d.source.y,
        dr = Math.sqrt(dx * dx + dy * dy);
      return "M" + d.source.x + "," + d.source.y + "A" + dr + "," + dr + " 0 0,1 " + d.target.x + "," + d.target.y;
    }

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      return "translate(" + d.x + "," + d.y + ")";
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  </script>
</body>

</html>